import 'dart:io';

void main() {
  // 提示用户输入月份
  print("请输入月份（1-12）：");
  
  // 获取用户输入的月份
  int month = int.parse(stdin.readLineSync()!);
  
  // 判断季节
  String season;
  if (month >= 1 && month <= 12) {
    if (month >= 2 && month <= 4) {
      season = "春季";
    } else if (month >= 5 && month <= 7) {
      season = "夏季";
    } else if (month >= 8 && month <= 10) {
      season = "秋季";
    } else {
      season = "冬季";
    }
    print("${month}月是${season}");
  } else {
    print("请输入有效的月份（1-12）！");
  }
}
